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Mao Ye

Publications and source records attributed to Mao Ye.

15 recordsLinked to original sources
PubMed2026

Comparative evaluation of chitosan-based and star polycation nanocarriers for enhanced RNAi efficacy targeting CmFibL in Cnaphalocrocis medinalis.

BACKGROUND: The rice leaf folder, Cnaphalocrocis medinalis, causes substantial rice yield losses through larval leaf-rolling behavior. RNA interference (RNAi) offers a sustainable alternative, but its application in Lepidoptera is hindered by dsRNA degradation and poor cellular uptake. This study developed nanocarrier-mediated dsRNA delivery to overcome these limitations. RESULTS: Three nanocarriers - chitosan (CS), chitosan-tripolyphosphate (CS-TPP), and star polycation (SPc) - were compared for enhancing RNAi efficiency targeting the C. medinalis fibroin light chain gene (CmFibL). CS-TPP and SPc achieved 61% and 55% silencing efficiency, respectively, representing 2.7-fold improvement over naked dsRNA (23%). All nanocarriers protected dsRNA from RNase A (30 min) and midgut fluid (6 h) degradation. CmFibL knockdown caused severe silk defects, prolonged pupal duration by 23%, reduced pupal weight by 33%, and decreased leaf-rolling damage by 31% in glasshouse cage trials. Transcriptomics revealed down-regulation of amino acid metabolism and activation of endoplasmic reticulum (ER) stress and immune responses. No off-target effects were detected in human genome, nor in any predators or parasitoids sharing the same ecological niche. CONCLUSION: CS-TPP and SPc nanocarriers effectively enhance RNAi efficiency in a Lepidopteran pest. Targeting CmFibL disrupts silk-mediated feeding shelters with minimal ecological risk, providing a practical framework for field application of RNAi-based biopesticides against leaf-rolling rice pests. © 2026 Society of Chemical Industry.

Animals↗
PubMed2007

The natural vegetation responses to the groundwater change resulting from ecological water conveyances to the lower Tarim River.

This paper takes the ecological water conveyance project (EWCP) that transfers water from the Bosten Lake, to Daxihaizi Reservoir, and finally to the Taitema Lake as a case study to analyze the dynamic change of the groundwater depth, the vegetation responses to the elevation of the groundwater depth as well as the relationship between the groundwater depth and the natural vegetation. The results from many years' monitoring in field indicate: (1) the groundwater depth has been elevating gradually with the increase in the times of watering and the elevation range has been expanding continuously in the lower reaches of Tarim River. Correspondingly, the natural vegetation has a favorable response to the elevation of the groundwater depth. The change of the natural vegetation has accordance with that of the groundwater depth. Such facts not only show that groundwater is a key factor to the growth of the native vegetation but also prove it is feasible that the degraded ecosystem can be restored and protected by the EWCP; (2) the results of analysis of the spatial-temporal response of the natural vegetation to watering reveals that the beneficial influence of the EWCP on the ecosystem in the lower Tarim River is a long-term process; (3) in terms of the function and structure of ecosystem after watering in the lower reaches of Tarim River, the EWCP does not still reach the goal of ecological restoration at a large spatial scale at present. Based on such monitoring results, some countermeasures and suggestions for the future restoration strategy are proposed so as to provide a theoretical basis for restoring and protecting the ecosystem in Tarim River, and meanwhile it can also provide some scientific references for implementing the similar ecological projects in other areas.

Agriculture↗
PubMed2006

Stimulation of P-glycoprotein ATPase by analogues of tetramethylrosamine: coupling of drug binding at the "R" site to the ATP hydrolysis transition state.

The multidrug resistance efflux pump P-glycoprotein (Pgp) couples drug export to ATP binding and hydrolysis. Details regarding drug trajectory, as well as the molecular basis for coupling, remain unknown. Nearly all drugs exported by Pgp have been assayed for competitive behavior with rhodamine123 transport at a canonical "R" drug binding site. Tetramethylrosamine (TMR) displays a relatively high affinity for Pgp when compared to other rhodamines. Here, we present the construction and characterization of a library of compounds based upon the TMR scaffold and use this set to assess the determinants of drug binding to the "R" site of Pgp. This set contained modifications in (1) the number, location, and conformational mobility of hydrogen-bond acceptors; (2) the heteroatom in the xanthylium core; and (3) the size of the substituent in the 9-position of the xanthylium core. Relative specificity for coupling to the distal ATP catalytic site was assessed by ATPase stimulation. We found marked ( approximately 1000-fold) variation in the ATPase specificity constant within the library of TMR analogues. Using established methods involving ADP-Vi trapping by wild-type Pgp and ATP binding by catalytic carboxylate mutant Pgp, these effects can be extended to ATP hydrolysis transition-state stabilization and ATP occlusion at a single site. These data support the idea that drugs trigger the engagement of ATP catalytic site residues necessary for hydrolysis. Further, the nature of the drug binding site and coupling mechanism may be dissected by variation of a drug-like scaffold. These studies may facilitate development of novel competitive inhibitors at the "R" drug site.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

Global convergence analysis of a discrete time nonnegative ICA algorithm.

When the independent sources are known to be nonnegative and well-grounded, which means that they have a nonzero pdf in the region of zero, Oja and Plumbley have proposed a "Nonnegative principal component analysis (PCA)" algorithm to separate these positive sources. Generally, it is very difficult to prove the convergence of a discrete-time independent component analysis (ICA) learning algorithm. However, by using the skew-symmetry property of this discrete-time "Nonnegative PCA" algorithm, if the learning rate satisfies suitable condition, the global convergence of this discrete-time algorithm can be proven. Simulation results are employed to further illustrate the advantages of this theory.

Letter↗
PubMed2006

A class of self-stabilizing MCA learning algorithms.

In this letter, we propose a class of self-stabilizing learning algorithms for minor component analysis (MCA), which includes a few well-known MCA learning algorithms. Self-stabilizing means that the sign of the weight vector length change is independent of the presented input vector. For these algorithms, rigorous global convergence proof is given and the convergence rate is also discussed. By combining the positive properties of these algorithms, a new learning algorithm is proposed which can improve the performance. Simulations are employed to confirm our theoretical results.

Algorithms↗
PubMed2005

Structure-activity studies of uptake and phototoxicity with heavy-chalcogen analogues of tetramethylrosamine in vitro in chemosensitive and multidrug-resistant cells.

Several thio and seleno analogues of tetramethylrosamine (TMR) were prepared. Thio derivatives of TMR have absorption maxima near 570 nm, while seleno derivatives of TMR have absorption maxima near 580 nm. The 3- or 4-N,N-dimethylaminophenyl substituent in the 9-position greatly increases internal conversion, which lowers quantum yields for fluorescence and the generation of singlet oxygen. Thio and seleno analogues of TMR are effective photosensitizers against chemosensitive AUXB1 cells in vitro and against multidrug-resistant CR1R12 cells in vitro, which have been treated with verapamil. The CR1R12 cells accumulated significantly lower concentrations of the photosensitizers relative to the AUXB1 cells presumably due to the expression of P-glycoprotein (Pgp) in the CR1R12 cells. Following treatment with 5 x 10(-5) M verapamil, the uptake in CR1R12 cells of several fluorescent thio analogues of TMR is comparable to that observed for the chemosensitive AUXB1 cells.

Animals↗
PubMed2005

Grifolin, a potential antitumor natural product from the mushroom Albatrellus confluens, inhibits tumor cell growth by inducing apoptosis in vitro.

Grifolin is a natural biologically active substance isolated from the fresh fruiting bodies of the mushroom Albatrellus confluens. Here, for the first time, we describe a novel activity of grifolin, namely its ability to inhibit the growth of tumor cells by the induction of apoptosis. Grifolin strongly inhibited the growth of tumor cell lines: CNE1, HeLa, MCF7, SW480, K562, Raji and B95-8. Analysis of acridine orange (AO)/ethidium bromide (EB) staining and flow cytometry showed that grifolin possessed apoptosis induction activity to CNE1, HeLa, MCF7 and SW480. Furthermore, the cytochrome c release from mitochondria was detected by confocal microscopy in CNE1 cells after a 12h treatment with grifolin. The increase of caspase-8, 9, 3 activities revealed that caspase was a key mediator of the apoptotic pathway induced by grifolin, and the underexpression of Bcl-2 and up-regulation of Bax resulted in the increase of Bax: Bcl-2 ratio, suggesting that Bcl-2 family involved in the control of apoptosis. Owing to the combination of the significant antitumor activity by inducing apoptosis and natural abundance of the compound, grifolin holds the promise of being an interesting antitumor agent that deserves further laboratory and in vivo exploration.

Animals↗
PubMed2005

Epstein-Barr virus encoded latent membrane protein 1 modulates nuclear translocation of telomerase reverse transcriptase protein by activating nuclear factor-kappaB p65 in human nasopharyngeal carcinoma cells.

Sustained proliferation of cancer cells requires that telomerase maintain chromosomal stability and prolong telomere length-regulated cell replication. Human telomerase reverse transcriptase (hTERT), the human telomerase catalytic subunit, and also the key determinant of the enzymatic activity of human telomerase, is regulated both at the transcriptional level and via phosphorylation and translocation. In this study, we show that latent membrane protein 1 (LMP1), the principal oncoprotein of Epstein-Barr virus (EBV), modulates telomerase activity by inducing the direct binding of hTERT to nuclear factor kappaB (NF-kappaB) p65 and translocation of both proteins from the cytoplasm to the nucleus in nasopharyngeal carcinoma cells (NPC). Conversely, a NF-kappaB nuclear translocation inhibitor, (benzylcarbonyl)-Leu-Leu-phenylalaninal (Z-LLF-CHO), and a dominant negative mutant of inhibitor of NFkappaB (IkappaBalpha), can block LMP1-induced hTERT nuclear translocation. These studies suggest a novel function of LMP1 and confirm that NF-kappaB plays an important role in regulating the activation and nuclear translocation of telomerase in NPC cells.

Antigens, Viral↗
PubMed2005

Effect of EBV LMP1 targeted DNAzymes on cell proliferation and apoptosis.

The latent membrane protein (LMP1) encoded by Epstein-Barr virus (EBV) has been suggested to be one of the major oncogenic factors in EBV-mediated carcinogenesis. RNA-cleaving DNA enzymes are catalytic nucleic acids that bind and cleave a target RNA in a highly sequence-specific manner. In this study, we explore the potential of using DNAzymes as a therapeutic approach to EBV-associated carcinomas by targeting the LMP1 gene. In all, 13 different phosphorothioate-modified "10-23" deoxyribozymes (DNAzymes) were designed and synthesized against the LMP1 mRNA and transfected into B95-8 cells, which constitutively express the LMP1. Fluorescence microscopy was used to examine the cellular uptake and distribution in B95-8 cells. As demonstrated in Western blots, three out of 13 deoxyribozymes significantly downregulated the expression of LMP1 in B95-8 cells. These DNAzymes were shown to markedly inhibit B95-8 cell growth compared with a disabled DNAzyme and untreated controls, as determined by an alamarBlue Assay. It was further demonstrated that these DNAzymes arrested the B95-8 cells in G0/G1 using flow cytometry. Interestingly, the active DNAzymes could also downregulate the expression of Bcl-2 gene in treated cells, suggesting a close association between the LMP1 and Bcl-2 genes and their involvement in apoptosis. This was further confirmed with the result that the DNAzymes could induce the release of cytochrome c from mitochondria, which is the hallmark of the apoptosis. The present results suggest that the LMP1 may present a potential target for DNAzymes towards the EBV-associated carcinoma through cell proliferation and apoptosis pathways.

Animals↗
PubMed2005

Convergence analysis of a deterministic discrete time system of Oja's PCA learning algorithm.

The convergence of Oja's principal component analysis (PCA) learning algorithms is a difficult topic for direct study and analysis. Traditionally, the convergence of these algorithms is indirectly analyzed via certain deterministic continuous time (DCT) systems. Such a method will require the learning rate to converge to zero, which is not a reasonable requirement to impose in many practical applications. Recently, deterministic discrete time (DDT) systems have been proposed instead to indirectly interpret the dynamics of the learning algorithms. Unlike DCT systems, DDT systems allow learning rates to be constant (which can be a nonzero). This paper will provide some important results relating to the convergence of a DDT system of Oja's PCA learning algorithm. It has the following contributions: 1) A number of invariant sets are obtained, based on which we can show that any trajectory starting from a point in the invariant set will remain in the set forever. Thus, the nondivergence of the trajectories is guaranteed. 2) The convergence of the DDT system is analyzed rigorously. It is proven, in the paper, that almost all trajectories of the system starting from points in an invariant set will converge exponentially to the unit eigenvector associated with the largest eigenvalue of the correlation matrix. In addition, exponential convergence rate are obtained, providing useful guidelines for the selection of fast convergence learning rate. 3) Since the trajectories may diverge, the careful choice of initial vectors is an important issue. This paper suggests to use the domain of unit hyper sphere as initial vectors to guarantee convergence. 4) Simulation results will be furnished to illustrate the theoretical results achieved.

Algorithms↗
PubMed2004

Effects of lycorine on HL-60 cells via arresting cell cycle and inducing apoptosis.

As a natural anti-cancer alkaloid extracted from Amaryllidaceae, lycorine shows various biological effects on tumor cells. The survival rate of HL-60 cells exposed to lycorine was decreased in a dose-dependent manner with 1 microM as the 50% inhibitory concentration (IC50), cell growth was slowed down by arresting cell cycle at G2/M phase, and cell regeneration potential was inhibited. HL-60 cells exhibited typical apoptotic morphological changes, apoptotic DNA "ladder" pattern, and sub-G1 peak in cell phase distribution, showing apoptosis of HL-60 cells. To further understand the apoptotic molecular mechanism of lycorine on HL-60 cells, caspase activity was tested by colorimetric assay, and the expression of Bcl-2 and Bax proteins was examined by Western blotting. The increase of caspase-8, -9, -3 activities demonstrated that caspase was a key mediator of apoptotic pathways induced by lycorine. Under-expression of Bcl-2 and increase of Bax:Bcl-2 ratio showed that Bcl-2 family proteins were involved in apoptosis. Our finding suggests that lycorine can suppress leukemia growth and reduce cell survival via arresting cell cycle and inducing apoptosis of tumor cells.

Amaryllidaceae Alkaloids↗
PubMed2004

Liquid-crystal lens with a focal length that is variable in a wide range.

A liquid-crystal (LC) lens driven by two voltages is reported. The lens has a focal length that is electrically tunable. The range of the variable focusing power is very wide, covering approximately 0.8-10.7 D. In the entire focal range the LC lens maintains high optical quality. The LC lens can be driven in a simple way to prevent the occurrence of a disclination line. The use of the LC lens in image formation is demonstrated.

Journal Article↗
PubMed2004

Induction of apoptosis by epigallocatechin-3-gallate via mitochondrial signal transduction pathway.

PURPOSE: To elucidate the apoptosis induction of Epigallocatechin-3-gallate (EGCG) on nasopharyngeal carcinoma (NPC) cells via mitochondrial signal transduction pathway regulated by EB-virus-encoded latent membrane protein 1 (LMP1). METHODS: The survival rates of pTet-on-LMP1 HNE2 cells after the EGCG treatment were determined by MTT assay. Induction of apoptosis in pTet-on-LMP1 HNE2 cells after the EGCG treatment was analyzed by agarose gel electrophoresis. The activity of caspase-9 was determined by ApoAlert Caspase-9 Fluorescent Assay kit after the EGCG treatment. The protein expressions of cytochrome c and Bcl-2 were analyzed by Western blotting after the EGCG treatment. RESULTS: EGCG inhibited the survival rates of pTet-on-LMP1 HNE2 cells and induced apoptosis of pTet-on-LMP1 HNE2 cells. EGCG raised the activities of caspase-9, enhanced the releasing of cytochrome c from the mitochondria, and suppressed the protein expression of Bcl-2. These are the key targets on the mitochondrial signal transduction pathway in apoptosis. CONCLUSIONS: EGCG inhibited the survival rate of NPC cells and induced apoptosis of NPC cells via the mitochondrial signal transduction pathway. This study suggests that the interference effect of EGCG on targets of the mitochondrial signal transduction pathway plays an important role in the anticancer function.

Anticarcinogenic Agents↗
PubMed2004

[Effects of the glucosidorum tripterygll totorum on the proliferation and apoptosis of cell line HL-60 in human acute promyelocytic leukemia].

OBJECTIVE: To determine the effects of the glucosidorum tripterygll totorum on the proliferation inhibition and apoptosis induction of cell line HL-60 in human acute promyelocytic leukemia. METHODS: The survival rates of cells were tested by MTT assay, fluorescence stain, flow cytometry test, and DNA fragmentation. RESULTS: Glucosidorum tripterygll totorum could notably reduce the survival rate of HL-60 cells, and inhibit the proliferation of tumor cells. The 50% inhibitory concentration (IC50) was 5.0 microg/ml and it arrested the cell cycle at G2/M phase (P < 0. 05). The typical apoptosis morphologic cells were seen, the rates of apoptosis cells were increased (P < 0.05), and DNA ladder appeared in the experiment group. CONCLUSION: Glucosidorum tripterygll totorum could notably inhibit the proliferation and induce the apoptosis of HL-60 cells.

Antineoplastic Agents, Phytogenic↗